High temperature refractory furnace

ABSTRACT

A furnace construction for a glass or metal melting furnace having an upper self-supporting overhead superstructure over and connectable to a lower demountable furnace melting section where the superstructure has an outer top metal shell and several layers of various heat insulating materials thereunder, such overhead superstructure shell including a central dome surrounded by a segmented breast wall of a truncated cone construction supported at the downwardly tapered wedge top by an exterior circular skew of segmented brick structure and outer metal bond held by press jack bolts on the top metal shell, the breast wall being bound at the bottom by transversely extending annular lintel segmented block arrangement dovetailed into the lower outer edge of the segmented breast wall and held by press jack bolts on the metal top shell, the metal shell being provided with circumferentially peripherally spaced water jackets between each connection of each lintel block with a respective jack bolt that is connected to the outer metal shell.

United States Patent [191 Kranjcich et al.

[ Apr. 30, 1974 HIGH TEMPERATURE REFRACTORY FURNACE [75] Inventors: Edward W. Kranjcich, Pittsburgh,

Pa.; John R. Masters, Joliet, Ill. [73] Assignee: Pullman Incorporated, Chicago, Ill.

[22] Filed: Dec. 20, 1972 [21] Appl. No.: 317,049

[52] US. Cl 432/247, 52/416, 110/99 R,

110/1 R, 432/248, 432/237 [51] Int. Cl. F27d l/02 [58] Field of Search 432/247-252,

432/258, 233, 237, 238, 119; 266/24, 33, 43; llO/l R, l A, l B, l L, 99; 52/84, 415, 416, 74], 546, 576; 49/54, 172

[56] References Cited UNITED STATES PATENTS 1,655,680 l/l928 Goodwillie llO/99 2,414,545 l/l947 Moore 110/99 2,822,768 2/1958 Bankley..... 432/252 2,186,740 l/1940 Teeters 432/237 2,236,920 1 4/194] Robertson 432/252 1,751,008 3/1930 LaFrance 432/248 1,686,387 10/1928 Loftus 432/248 3,489,401 l/197O Merdian et al. 432/252 1,447,682 3/1923 Moats 432/250 Primary ExaminerJohn J. Camby Assistant Examiner-l-lenry C. Yuen Attorney, Agent, or FirmRichard J. Myers A furnace construction for a glass or metal melting furnace having an upper self-supporting overhead superstructure over and connectable to a lower demountable furnace melting section where the superstructure has an outer top metal shell and several layers of various heat insulating materials thereunder, such overhead superstructure shell including a central dome surrounded by a segmented breast wall of a truncated cone construction supported at the downwardly tapered wedge top by an exterior circular skew of segmented brick structure and outer metal bond heldby press jack bolts on the top metal shell, the breast wall being bound at the bottom by transversely extending annular lintel segmented block arrangement dovetailed into the lower outer edge of the segmented breast wall and held by press jack bolts on the metal top shell, the metal shell being provided with circumferentially peripherally spaced water jackets between each connection of each lintel block with a respective jack bolt that is connected to the outer metal shell.

29 Claims,6 Drawing Figures BACKGROUND OF THE INVENTION- 1. Field of the Invention This invention relates to the field of furnace construction and in particular to the construction of high temperature refractory furnaces for the melting of glass or metal or the like.

2. Description of the Prior Art In the construction of high temperature furnaces of the type referred to above, it is common practice to divide the furnace into an upper roof or superstructure section and a lower hearth or melting section whereby the melting section may be removed and replaced by another melting section while maintaining the upper section intact. The lower melting section must be replaced more frequently due to excessive wear from glass or metal contact on the refractories. It is highly desirable to provide for a furnace where the bottom or melting section may readily be removed while the top or superstructure section remains in place where the superstructure interior dome breast'wall and crown portions are so held and attached to the outer shell of the superstructure as to be self-supporting in the open furnace structure position of the superstructure when the demountable melting section is removed. Further, it is desirable to provide for appropriate water cooling to prevent deformation or destruction of metal members buried in the insulation of the superstructure, such deformation or destruction being liable to result in a hazard due to possible steam explosion from leaks in the water jackets. Further, it is desirable to provide water cooling at the base of the refractory where a lintel arrangement for support would place too great of a thermal gradient'through the refractory material at the lower portion of the superstructure section. It is the intent, spirit and purpose of this invention to provide for a furnace superstructure construction to overcome these objectionable difficulties.

SUMMARY The intent and purpose of this invention is to provide a unique method of supporting a refractory superstructure section over a removable lower or melting section of a high temperature furnace. The superstructure comprises an upper portion of the furnace for melting glass, ceramics, or metals. The inventive concept is specifically applied but not necessarily limited to the superstructure of the furnace where the interior ambient temperatures may be in excess of 3,200Fahrenheit, and where the superstructure section and the melting section must be separable from one another on a horizontal plane described by the interface or parting line between the superstructure and melting sections for rapid replacement of the melting section with a prebuilt unit. The furnace dome is supported by a breast wall which in turn is supported by a skew section or crown connecting with press jack bolts connecting with the outer metal shell where the breast wall is provided with an upper tapered or wedge shaped portion between the skew crown and the dome and where the lower portion of the breast wall is held by the peripherally located radially inwardly extending lintel blocks in binding fashion for the truncated cone-shaped breast wall. The lintel block arrangement further forms a closure at the bottom of the breast wall and connects with the outer shell of the superstructure section. This design is especially adaptable to furnaces requiring several layers of various insulating materials to prevent high heat losses from the furnace walls where the superstructure must be self-supporting due to the demountable melting section and where water cooling is necessary to prevent deformation or destruction to the metal members buried in the insulation and where water cooling is applied to the base of the refractory in the area of the connection of the lower part of the metal shell section by lintel blocks to the lower part of the breast plate. Cooling in the area of the lintel blocks eliminates the problem providing too great of a thermal gradient or too sharp of an exposure of the water to the refractory breast wall. It is to be further noted that the top of the superstructure side walls form a skew surface used in the crown, that is the outer metal wall portion of the superstructure adjacent the crown is skewed and jack bolts through it press against the skewed blocks of the crown in aid of holding the downwardly tapered upper part of the breast wall against the dome portion of the superstructure section. Construction of the lintel portion of the superstructure is of segmented block design dovetailed into the lower outer edge of the segmented breast wall and a plurality of peripherally spaced water jackets are located peripherally between the connection of each lintel block with a respective jack bolt that is connected to the outer metal shell.

These and other objects and advantages will become apparent from reference to the following description, appended claims and attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view of the furnace arrangement;

FIG. 2 is a top plan view of thefurnace arrangement;

FIG. 3 is an end elevational view of the furnace arrangement;

FIG. 4 is a side elevational view in section of the furnace proper; 1 FIG. 5 is an enlarged partial sectional view of the lintel crown and breast wall portions of the superstructure section of the furnace; and

FIG. 6 is a sectional view taken approximately along line 6-6 of FIG. 5.

DESCRIPTION OF THE PREFERRED EMBODIMENT With reference now to the drawings and in particular with reference to FIGS. 1-3, there is shown a high temperature melting refractory furnace arrangement 2 which includes a furnace proper or body 4 which is generally circular in top plan viewing. An upright ladder 6 is positioned along the side of the furnace and leads to an upper inspection deckor platform 8 surrounded by a railing 7. The ladder and deck are supported by support columns 9 and 11. The furnace 4 is supported by support and pivot structure 10 which includes two pivot support columns or legs 24 and 25 and two pivot support standards 26 and 27 to be described later. The furnace 4 includes a top portion or superstructure section 12 and a lower or bottom removable melting section 14. When the upper and lower sections are in place they are held together by bolt means 16 as best seen in FIG. 1 which includes an upper bolt 16a on the upper furnace, nut 16b and bracket 16c on the lower furnace. The upper refractory or superstructure section 12 is provided in its top with a central material loading or charge inlet means 18 and a furnace pouring spout structure 20 is provided on the end of the furnace along its curved vertical outer walls at the parting line or interface 22. The furnace 4 is thus held by the legs 24, and the pivot standards 26, 27 on the ground 23.

Each pivot support column or leg 24 or 25 at its upper portion carries its respective elevating nut structure 28 which includes a nut 30 pivotally carried by nut elevated section 32 on pivot pins 34. Each nut elevated section 32 is provided with upper and lower fingers or flanges 36, 37. The upper portion 38 of each leg 24 or 25 is threaded to receive threaded nut 30 and the lower shaft portion 40 of each column includes a screw rotating support base 42 and a rotator 44 to rotate the column 24 or 25 and a leg or column pivot pin structure 46 to allow for some arcuate movement of the nut structure 28. Each pivot support standard 26 or 27 is provided with a pivot arm 48 at its upper end which can pivot by pivot pin 50 relative to the lower fixed standard part 54 and is provided with upper and lower fingers or flanges 52, 53 for complemental engagement with the fingers or flanges 36, 37 of the elevating nut structure 28 which when operated by rotation of the shaft 40 will cause tilting of the upper superstructure section 12 relative to the removable bottom section 14 about the pivot pin 50 upward about 8 inclination above the horizontal as shown in FIG. 1. With the upper section of the furnace tilted upwardly and away from the lower section, the lower section may be removed by a transfer car and a new bottom or melting section 68 (shown in phantom) may be moved underneath the upper furnace section by the transfer car 56 which is also shown in phantom and is provided with wheels 58 for ground track 70 and comprises a longitudinal member 59 and a skid and loading and unloading frame 60 with crossmembers 61 being provided with jack means 62 including jack elements 63 connected by shafts 64 and driven by crank drive mechanism 64a on support 65 by the motor and drive structure 66 which places the new lower section into position and then the upper section may be lowered on it and bolted down by bolts 16.

Attention is now directed to FIGS. 4-6 of the drawings where the upper and lower sections of the furnace are shown in cross-section. The upper or superstructure section 12 is provided with a generally cylindrical shaped metal lining 72 of 34 inch steel plate and includes, as seen on the lower left-hand side of the drawing of FIG. 5, a vertically but downwardly tapered section 72a and a horizontally directed flange section 72b and, as further seen in FIG. 4, the upper radiant side of the furnace shell 72 is shown diverging downwardly and is provided with a spout water jacket 136 thereabout. The metal lining 72 further includes the flat top or roof section 73. Inside of this cap lining 72 is provided at the very top loose insulating fiber in the spaces just below the roof. The wool-like fiber 74 surrounds the loading or charge inlet means 18 as does the blanket 76 of fiber of highly thermal insulatory material. Below the blanket 76 is located the castable insulating material 78 which is surrounded by the blanket 76. The castable insulating material is an aluminum oxide refractory which is dense and adds support to the annular breast wall 82. Below the castable 78 is located the central annular or circular dome 80 of fuse cast material which is a highly dense refractory.

The dome 80 is the central portion of an arcuate shaped structure consisting of the dome 80, the breast wall 82 and the outer skewed crown portion 84 and in elevation the dome is annular and is surrounded by the breast wall 82 which supports it which in turn is surrounded by the skew crown structure 84 which surrounds the breast wall. The three annular structures, 80, 82 and 84 have their top portions against the castable insulating material 78 with the dome embracing and surrounding the lower portion of the inlet means 18. It will be noted that, as viewed in FIG. 4, the right face of the dome member 80 is vertically flush with the inlet means 18 but that the left face is skewed or tapered downwardly and to the right which also makes the upper portion 92 of the breast wall 82 have a right skewed or tapered face abutting the dome 80 and the left wall of the upper portion 92 of the breast wall 82 is also skewed or tapered so that the right and left walls or the inner and outer surfaces of the annular upper portion 92 of the breast wall is wedge-shaped or tapered. Looking at FIG. 4 it is seen that there is a dimension shown as d at the upper part of the upper portion 92 of the breast wall 82 and at the lower part of the upper portion 92 there is shown a dimension D. The dimension d at the top is of greater length than the dimension D at the bottom to illustrate that the upper portion 92 is tapered. However, the lower depending portion 94 of the breast wall 82 which depends from the upper portion and extends below the dome 80 and the skew plated crown 82 has more or less parallel inner and outer sides or surfaces and, therefore, the distance D across the top of the lower portion 94 is uniform all the way down the extent of lower breast wall portion 94, as best seen in FIG. 5. The breast wall 82 is made up of segmental blocks in a circular path and when placed together form a truncated cone. The cone is supported at the top by the skewmost inner skew crown segment 86 of the crown structure 84 and as noted in FIGS. 4 and 5, each skew segment is provided with skew inner and outer surfaces adjacent each other as they proceed outwardly toward the skew tightening bolts 87. That is to say that their inner and outer downwardly vertically extending surfaces are actually extending in a sloping direction downwardly to the right but the inner and outer surfaces of the skew segments are generally parallel to one another. Thus the cone is supported at the top by a skew crown which is made up of several layers 86 of annularly stacked segmented bricks laid up to form a bearing which supports the breast wall 82 at the top and the crown jack bolts 87, 87 are snugged up against the crown skew plate 91 adjacent the outermost skew crown unit 86, the skew plate being at the same skew angle as are the skew layers 86. Like the dome, the breast wall and the skew crown are made of fused cast, the highly thermal insulating alumina material. Like the breast wall the skew crown is circumferentially disposed about the inlet means 18. The skew bolts 87 are tightened up against the skew plate 91 by the skew tightening nuts 89. The inlet means 18 includes the upper annular inner member 88 of fused cast refractory type material and about this inner member 88 is the outer annulus or ring 90 of fused cast refractory type material. The lower depending portion 94 of the breast wall 88 is notched out at its lower outer end to receive the lintel block structure 96. This is best seen in FIG. 5 where the particular lintel block has an inner edge 98 which includes an upper end edge 98a and a lower downwardly sloped face 98b to be received in the complemental horizontal bottom surface 100a and the tapered vertical surface 100k of the cutout portion 100 in each breast wall portion. Like the segmented breast wall structure 82, the lintel blocks form a plurality of arcuate radially extending segments 96 about the outer peripheral portions of the furnace as best seen inFIG. 6. Each lintel block 96 has at its outer end a stop plate structure 102 which includes an outer.vertical plate 102a, an intermediate heat insulation material 1020 and an inner plate 102b against the outer peripheral edge of the lintel block 96. The stop plate structure 102 further includes a lintel tightening bolt 104, the inner edge of which presses against the plate 102a and the bolt 104 has a tightening nut 106 on it and bearing against the outside lower metal plate portion 72a of the metal outer shell 72 of the top of the furnace. By such an arrangement the lintel blocks can be pressed against the lower outer corners of the breastwall segments 82 and thereby form a closure at the bottom of the breast wall structure and also serve as a binding block arrangement for a truncated cone arrangement of the breast wall structure.

As seen in FIGS. 5 and 6', there are provided a plurality of water jackets 105 with inlets 105a and l05b alternately placed between the lintel tightening bolts 104 against the outer metal wall 72 of the furnace. Each water jacket 105 is defined by the metal lining 107 and has water passages 107a within it. it willbe noted that the water jackets 105 are spaced away from the highly heated refractory material such as that at the breast wall and since we cool at the outer surface and the water is removed outwardly away from the hearth area the water will not be exposed to high temperature material and, therefore, cause an explosion and each of the lintel blocks provides for a thermal gradient between the water jacket and the breast wall which is gradual and, therefore, there cannot be any steam explosions which would be undesirable and, of course, dangerous.

The bottom part of the lower melting unit comprises a lower outer metal jacket 108 of steel above which is a fiber insulating liner 110 and above that is an outer layer of insulating fire brick 112 and above that is an inner layer of insulating fire brick 114 and above that and adjacent the melting area is a layer of zircon oxide 116 upon which rests isostatically pressed zircon 118 which forms the hearth or melting pot area for the molten material and which contains the downwardly extending drain plug 124 with a drain passage 122 therein and the passage has a drain plug retainer 126 which may be removed when it is desired to drain the furnace of its material. Tuyeres or burners 128 are located coming out of the lower portion 94 of the breast wall 82 for heating the furnace. The pouring spout structure 20 is provided with a spout roof 130 of fused cast refractory material and a spout floor 131 which is sloped and is made of zircon which leads to the hearth or furnace bed 132 above which is disposed the furnace cavity or interior 134. The pouring spout cooling jacket 136 of metal lining is provided with the water passage 138 to provide cooling for the spout structure 20.

Thus what is provided is an annular dome structure in a furnace surrounded by an upper tapered breast wall that is supported by an annular skew crown portion all pressed together by jack bolts mounted on the outer shell of the upper furnace portion wherein there is provided an annular lintel structure bindingly supporting the lower portion of the breast wall and being pressed against it by jack bolts attached to the metal lining alternately spaced with circumferentially arranged water cooling jackets to provide for desirable gradual thermal cooling radients.

The foregoing description and drawings merely explain and illustrate the invention and the invention is not limited thereto, except insofar as the appended claims are so limited, as those skilled in the art who have the disclosure before them will be able to make modifications and variations therein without departing from the scope of the invention.

What is claimed is:

1. A furnace construction for a high temperature melting furnace having a demountable furnace melting section and a self-supporting superstructure over and releasably connectable to the demountable furnace melting section and forming a parting line therewith,

the superstructure including a top outer meta] shell and several layers of various heat insulating materials thereunder and a central refractory dome structure below said layers,

a segmented refractory breast wall of a truncated cone surrounding said dome structure and having an upper downwardly tapered section and a lower lintel engaging section,

an exterior circular skew crown of segmented brick construction surrounding and supporting the upper section of said breast wall,

transversely extending annular lintel blocks bindingly engaging the lower outer edge of the segmented breast wall,

press jack bolt means connecting the lintel blocks with the metal shell pressing the lintel blocks into binding relation with the breast wall, and

the outer metal shell being provided with circumferentially peripherally spaced water jackets each being between two adjacent lintel press jack bolt means.

2. A furnace construction for a melting furnace having a demountable furnace melting section and a selfsupporting superstructure over and releasably connectable to the demountable furnace melting section and forming a parting line therewith,

the superstructure including a top outer metal shell and several layers of various heat insulating materials thereunder and a central refractory dome structure below said layers,

a segmented refractory breast wall having an upper section surroundingsaid dome structure and having a lower lintel engaging section,

an exterior circular skew crown of segmented brick construction surrounding and supporting the upper section of said breast wall,

transversely extending annular lintel blocks bindingly engaging the lower outer edge of the segmented breast wall.

3. A furnace construction for a melting furnace having a demountable furnace melting section and a selfsupporting superstructure over and releasably connectable to the demountable furnace melting section and forming a parting line therewith,

the superstructure including a top outer metal shell and several layers of various heat insulating materials thereunder and a central refractory dome structure below said layers,

a segmented refractory breast wall having an upper section surrounding said dome structure and having a lower lintel engaging section,

an exterior circular skew crown of segmented brick construction surrounding and supporting the upper section of said breast wall,

said breast wall having tapered wedge section being wider at the top than at the bottom thereof being wedged between the outer periphery of the dome structure and inner periphery of the skew crown.

4. The invention according to claim 2, and

press jack bolt means connecting the lintel blocks with the metal shell pressing the lintel blocks into binding relation with the breast wall.

5. The invention according to claim 2, and

means on the shell binding the lintel blocks with the breast wall.

6. The invention according to claim 2, and

cooling means adjacent the lintel blocks at the metal shell for providing a cooling gradient for the breast wall.

7. The invention according to claim 4, and

the outer metal shell being provided with circumferentially peripherally spaced water jackets each being between two adjacent lintel press jack bolts.

8. A furnace construction for a melting furnace having a melting section and a ground supported superstructure over and releasably connectable to the demountable melting section, the superstructure comprising:

a top outer shell having a top portion and side portions and an annular central dome section being below the shell top portion,

an annular breast wall being outwardly of and engagingly surrounding the dome section and comprised of a plurality of circumferentially arrayed segments,

said breast wall having an upper annular portion in alignment with the dome section and a lower annular depending portion extending outward and below the dome section,

an annular skew crown within the side portions surrounding the breast wall and engaging the outer part of the upper breast wall portion, and

means on the side portions engaging with the outer peripheral portions of the crown whereby the dome section, breast wall and crown are suspended from the shell of the ground supported superstructure.

9. The invention according to claim 8, and

said means on the side portions comprising tie means compressing the skew crown against the breast wall and dome section.

10. The invention according to claim 8, and

said crown comprising a plurality of radially spaced back-to-back placed annular skew segments.

11. The invention according to claim 10, and

each skew segment comprising a plurality of circumferentially arranged blocks abutting one another.

12. The invention according to claim 10, and

each of said skew crown segments being generally parallel to one another in arching fashion and being in askew butting relation with the upper breast wall portion which is in turn in askew butting relation with the dome section.

13. The invention according to claim 9, and

the upper breast wall portion having its inner and outer peripheral surfaces in askew relation with the complementally engaging surfaces of the dome section and crown,

said inner and outer surfaces tapering downwardly toward one another to lift a wedge shaped upper breast wall portion which cannot fall from its entrapment with the dome section and crown.

14. The invention according to claim 8, and

the upper breast wall portion having its inner and outer peripheral surfaces in askew relation with the complementally engaging surfaces of the dome section and crown,

said inner and outer surfaces tapering downwardly toward one another to lift a wedge shaped upper breast wall portion which cannot fall from its entrapment with the dome section and crown.

15. The invention according to claim 9, and

said tie means being press jack bolts mounted on the shell and engaging a skew plate on the outer periphery of the skew crown.

16. The invention according to claim 8, and

an elongated radially extending generally annular lintel block structure generally peripherally surrounding the lower breast wall portion inwardly of the shell side portions and bindingly engaging said lower breast wall portion.

17. The invention according to claim 16, and

lintel tie means connecting with the side portions and compressing the lintel structure into the lower breast wall portion.

18. The invention according to claim 17, and

said means on the side portions comprising press iack bolts mounted on the side portions and engaging the outer periphery of the lintel structure and forcing the lintel structure into binding abutting relation against the lower breast wall portion.

19. The invention according to claim 16, and

said lintel structure having a wedging dovetail inner end with a taper face for engagement with the I lower breast wall portion and said lower breast wall portion having a lower outer peripheral cutout portion complementally dovetailing with the inner end and its taper face in aid of bindingly supporting the breast wall by the lintel structure.

20. The invention according to claim 16, and

said annular lintel structure including a plurality of circumferentially abutting blocks, and a plurality of peripherally arranged tie means about said lintel structure, there being a complemental tie means for each lintel block, each said tie means being on the side portion and engaging a respective lintel block and urging the lintel block into binding with the lower portion of the breast wall.

21. The invention according to claim 20, and

individual cooling means alternately and peripherally disposed about the shell between each two tie means.

22. The invention according to claim 21, and

each said cooling means including an individual water jacket.

23. A furnace construction for a melting furnace having a melting section and a ground supported superstructure over and releasably connectable to the demountable melting section, the superstructure comprisa top outer shell having a top portion and side portions and an annular central dome section being below the shell top portion,

an annular breast wall being outwardly of and engagingly surrounding the dome section and comprised of a plurality of circumferentially arrayed segments,

said breast wall having an upper annular portion in alignment with the dome section and a lower annular depending portion extending outward and below the dome section,

an annular skew crown within the side portions surrounding the breast'wall and engaging the outer part of the upper breast wall portion, and

means on the side portions engaging with the outer peripheral portions of the crown whereby the dome section, breast wall and crown are suspended from the shell of the ground supported superstructure,

said means on the side portions comprising tie means compressing the skew crown against the breast wall and dome section,

said crown comprising a plurality of radially spaced back-to-back placed annular skew segments,

each skew segment comprising a plurality of circumferentially arranged blocks abutting one another.

24. A furnace construction for a melting furnace having a melting section and a ground supported superstructure over and releasably connectable to the demountable melting section, the superstructure comprising:

a top outer shell having a top portion and side portions and an annular central dome section being below the shell top portion,

an annular breast wall being outwardly of and engagingly surrounding the dome section and comprised of a plurality of circumferentially arrayed segments,

said breast wall having an upper annular portion in alignment with the dome section and a lower annular depending portion extending outward and below the dome section,

an annular skew crown within the side portions surrounding the breast wall and engaging the outer part of the upper breast wall portion, and 7 means on the side portions engaging with the outer peripheral portions of the crown whereby the dome section, breast wall and crown are suspended from the shell of the ground supported superstructure,

said means on the side portions comprising tie means compressing the skew crown against the breast wall and dome section,

said crown including skew segments, each of said skew crown segments being generally parallel to one another in arching fashion and being in askew butting relation with the upper breast wall portion which is in turn in askew butting relation with the dome section.

25. A furnace construction for a melting furnace having a melting section and a ground supported superstructure over and releasably connectable to the demountable melting section, the superstructure comprismg:

a top outer shell having a top portion and side portions and an annular central dome section being below the shell top portion,

an annular breast wall being outwardly of and engagingly surrounding the dome section and comprised of, a plurality of circumferentially arrayed segments,

said breast wall having an upper annular portion in alignment with the dome section and a lower annular depending portion extending outward and below the dome section,

an annular skew crown within the side portions surrounding the breast wall and engaging the outer part of the upper breast wall portion, and

means on the side portions engaging with the outer peripheral portions of the crown whereby the dome section, breast wall and crown are suspended from the shell of the ground supported superstructure,

said means on the side portions comprising tie means compressing the skew crown against the breast wall and dome section,

said crown having skew segments, each of said skew crown segments being generally parallel to one another in arching fashion and being in askew butting relation with the upper breast wall portion which is in turn in askew butting relation with the dome section,

the upper breast wall portion having its inner and outer peripheral surfaces in askew relation with the complementally engaging surfaces of the dome section and crown,

said inner and outer surfaces tapering downwardly toward one another to lift a wedge shaped upper breast wall portion which cannot fall from its entrapment with thedome section and crown.

26. The invention according to claim 25, and

an elongated radially extending generally annular lintel block structure generally peripherally surrounding the lower breast wall portion inwardly of the shell side portions and bindingly engaging said lower breast wall portion.

27, The invention according to claim 26, and

lintel tie means connecting with the side portions and compressing the lintel structure into the lower breast wall portion.

28. The invention according to claim 25, and

an elongated radially extending generally annular lintel block structure generally peripherally surrounding the lower breast wall portion inwardly of the shell side portions and bindingly engaging said lower breast wall portion,

said lintel structure having a wedging dovetail inner end with a taper face for engagement with the lower breast wall portion and said lower breast wall portion having a lower outer peripheral cutout portion complementally dovetailing with the inner end and its taper face in aid of bindingly supporting the breast wall by the lintel structure.

29. The invention according to claim 25, and

an elongated radially extending generally annular lintel block structure generally peripherally surrounding the lower breast wall portion inwardly of the shell side portions and bindingly engaging said lower breast wall portion,

said annular lintel structure including a plurality of circumferentially abutting blocks, and a plurality of peripherally arranged tie means about said lintel structure, there being a complemental tie means for each lintel block, each said tie means being on the side portions and engaging a respective lintel the lower portion of the breast wall. 

1. A furnace construction for a high temperature melTing furnace having a demountable furnace melting section and a selfsupporting superstructure over and releasably connectable to the demountable furnace melting section and forming a parting line therewith, the superstructure including a top outer metal shell and several layers of various heat insulating materials thereunder and a central refractory dome structure below said layers, a segmented refractory breast wall of a truncated cone surrounding said dome structure and having an upper downwardly tapered section and a lower lintel engaging section, an exterior circular skew crown of segmented brick construction surrounding and supporting the upper section of said breast wall, transversely extending annular lintel blocks bindingly engaging the lower outer edge of the segmented breast wall, press jack bolt means connecting the lintel blocks with the metal shell pressing the lintel blocks into binding relation with the breast wall, and the outer metal shell being provided with circumferentially peripherally spaced water jackets each being between two adjacent lintel press jack bolt means.
 2. A furnace construction for a melting furnace having a demountable furnace melting section and a self-supporting superstructure over and releasably connectable to the demountable furnace melting section and forming a parting line therewith, the superstructure including a top outer metal shell and several layers of various heat insulating materials thereunder and a central refractory dome structure below said layers, a segmented refractory breast wall having an upper section surrounding said dome structure and having a lower lintel engaging section, an exterior circular skew crown of segmented brick construction surrounding and supporting the upper section of said breast wall, transversely extending annular lintel blocks bindingly engaging the lower outer edge of the segmented breast wall.
 3. A furnace construction for a melting furnace having a demountable furnace melting section and a self-supporting superstructure over and releasably connectable to the demountable furnace melting section and forming a parting line therewith, the superstructure including a top outer metal shell and several layers of various heat insulating materials thereunder and a central refractory dome structure below said layers, a segmented refractory breast wall having an upper section surrounding said dome structure and having a lower lintel engaging section, an exterior circular skew crown of segmented brick construction surrounding and supporting the upper section of said breast wall, said breast wall having tapered wedge section being wider at the top than at the bottom thereof being wedged between the outer periphery of the dome structure and inner periphery of the skew crown.
 4. The invention according to claim 2, and press jack bolt means connecting the lintel blocks with the metal shell pressing the lintel blocks into binding relation with the breast wall.
 5. The invention according to claim 2, and means on the shell binding the lintel blocks with the breast wall.
 6. The invention according to claim 2, and cooling means adjacent the lintel blocks at the metal shell for providing a cooling gradient for the breast wall.
 7. The invention according to claim 4, and the outer metal shell being provided with circumferentially peripherally spaced water jackets each being between two adjacent lintel press jack bolts.
 8. A furnace construction for a melting furnace having a melting section and a ground supported superstructure over and releasably connectable to the demountable melting section, the superstructure comprising: a top outer shell having a top portion and side portions and an annular central dome section being below the shell top portion, an annular breast wall being outwardly of and engagingly surrounding the dome section and comprised of a plurality of circumferentially arrayed segmenTs, said breast wall having an upper annular portion in alignment with the dome section and a lower annular depending portion extending outward and below the dome section, an annular skew crown within the side portions surrounding the breast wall and engaging the outer part of the upper breast wall portion, and means on the side portions engaging with the outer peripheral portions of the crown whereby the dome section, breast wall and crown are suspended from the shell of the ground supported superstructure.
 9. The invention according to claim 8, and said means on the side portions comprising tie means compressing the skew crown against the breast wall and dome section.
 10. The invention according to claim 8, and said crown comprising a plurality of radially spaced back-to-back placed annular skew segments.
 11. The invention according to claim 10, and each skew segment comprising a plurality of circumferentially arranged blocks abutting one another.
 12. The invention according to claim 10, and each of said skew crown segments being generally parallel to one another in arching fashion and being in askew butting relation with the upper breast wall portion which is in turn in askew butting relation with the dome section.
 13. The invention according to claim 9, and the upper breast wall portion having its inner and outer peripheral surfaces in askew relation with the complementally engaging surfaces of the dome section and crown, said inner and outer surfaces tapering downwardly toward one another to lift a wedge shaped upper breast wall portion which cannot fall from its entrapment with the dome section and crown.
 14. The invention according to claim 8, and the upper breast wall portion having its inner and outer peripheral surfaces in askew relation with the complementally engaging surfaces of the dome section and crown, said inner and outer surfaces tapering downwardly toward one another to lift a wedge shaped upper breast wall portion which cannot fall from its entrapment with the dome section and crown.
 15. The invention according to claim 9, and said tie means being press jack bolts mounted on the shell and engaging a skew plate on the outer periphery of the skew crown.
 16. The invention according to claim 8, and an elongated radially extending generally annular lintel block structure generally peripherally surrounding the lower breast wall portion inwardly of the shell side portions and bindingly engaging said lower breast wall portion.
 17. The invention according to claim 16, and lintel tie means connecting with the side portions and compressing the lintel structure into the lower breast wall portion.
 18. The invention according to claim 17, and said means on the side portions comprising press jack bolts mounted on the side portions and engaging the outer periphery of the lintel structure and forcing the lintel structure into binding abutting relation against the lower breast wall portion.
 19. The invention according to claim 16, and said lintel structure having a wedging dovetail inner end with a taper face for engagement with the lower breast wall portion and said lower breast wall portion having a lower outer peripheral cutout portion complementally dovetailing with the inner end and its taper face in aid of bindingly supporting the breast wall by the lintel structure.
 20. The invention according to claim 16, and said annular lintel structure including a plurality of circumferentially abutting blocks, and a plurality of peripherally arranged tie means about said lintel structure, there being a complemental tie means for each lintel block, each said tie means being on the side portion and engaging a respective lintel block and urging the lintel block into binding with the lower portion of the breast wall.
 21. The invention according to claim 20, and individual cooling means alternately and peripherally disposed about the shell between Each two tie means.
 22. The invention according to claim 21, and each said cooling means including an individual water jacket.
 23. A furnace construction for a melting furnace having a melting section and a ground supported superstructure over and releasably connectable to the demountable melting section, the superstructure comprising: a top outer shell having a top portion and side portions and an annular central dome section being below the shell top portion, an annular breast wall being outwardly of and engagingly surrounding the dome section and comprised of a plurality of circumferentially arrayed segments, said breast wall having an upper annular portion in alignment with the dome section and a lower annular depending portion extending outward and below the dome section, an annular skew crown within the side portions surrounding the breast wall and engaging the outer part of the upper breast wall portion, and means on the side portions engaging with the outer peripheral portions of the crown whereby the dome section, breast wall and crown are suspended from the shell of the ground supported superstructure, said means on the side portions comprising tie means compressing the skew crown against the breast wall and dome section, said crown comprising a plurality of radially spaced back-to-back placed annular skew segments, each skew segment comprising a plurality of circumferentially arranged blocks abutting one another.
 24. A furnace construction for a melting furnace having a melting section and a ground supported superstructure over and releasably connectable to the demountable melting section, the superstructure comprising: a top outer shell having a top portion and side portions and an annular central dome section being below the shell top portion, an annular breast wall being outwardly of and engagingly surrounding the dome section and comprised of a plurality of circumferentially arrayed segments, said breast wall having an upper annular portion in alignment with the dome section and a lower annular depending portion extending outward and below the dome section, an annular skew crown within the side portions surrounding the breast wall and engaging the outer part of the upper breast wall portion, and means on the side portions engaging with the outer peripheral portions of the crown whereby the dome section, breast wall and crown are suspended from the shell of the ground supported superstructure, said means on the side portions comprising tie means compressing the skew crown against the breast wall and dome section, said crown including skew segments, each of said skew crown segments being generally parallel to one another in arching fashion and being in askew butting relation with the upper breast wall portion which is in turn in askew butting relation with the dome section.
 25. A furnace construction for a melting furnace having a melting section and a ground supported superstructure over and releasably connectable to the demountable melting section, the superstructure comprising: a top outer shell having a top portion and side portions and an annular central dome section being below the shell top portion, an annular breast wall being outwardly of and engagingly surrounding the dome section and comprised of a plurality of circumferentially arrayed segments, said breast wall having an upper annular portion in alignment with the dome section and a lower annular depending portion extending outward and below the dome section, an annular skew crown within the side portions surrounding the breast wall and engaging the outer part of the upper breast wall portion, and means on the side portions engaging with the outer peripheral portions of the crown whereby the dome section, breast wall and crown are suspended from the shell of the ground supported superstructure, said means on the side portions comprising tie means compressing the skew crown against the breast wall and dome section, said crown having skew segments, each of said skew crown segments being generally parallel to one another in arching fashion and being in askew butting relation with the upper breast wall portion which is in turn in askew butting relation with the dome section, the upper breast wall portion having its inner and outer peripheral surfaces in askew relation with the complementally engaging surfaces of the dome section and crown, said inner and outer surfaces tapering downwardly toward one another to lift a wedge shaped upper breast wall portion which cannot fall from its entrapment with the dome section and crown.
 26. The invention according to claim 25, and an elongated radially extending generally annular lintel block structure generally peripherally surrounding the lower breast wall portion inwardly of the shell side portions and bindingly engaging said lower breast wall portion.
 27. The invention according to claim 26, and lintel tie means connecting with the side portions and compressing the lintel structure into the lower breast wall portion.
 28. The invention according to claim 25, and an elongated radially extending generally annular lintel block structure generally peripherally surrounding the lower breast wall portion inwardly of the shell side portions and bindingly engaging said lower breast wall portion, said lintel structure having a wedging dovetail inner end with a taper face for engagement with the lower breast wall portion and said lower breast wall portion having a lower outer peripheral cutout portion complementally dovetailing with the inner end and its taper face in aid of bindingly supporting the breast wall by the lintel structure.
 29. The invention according to claim 25, and an elongated radially extending generally annular lintel block structure generally peripherally surrounding the lower breast wall portion inwardly of the shell side portions and bindingly engaging said lower breast wall portion, said annular lintel structure including a plurality of circumferentially abutting blocks, and a plurality of peripherally arranged tie means about said lintel structure, there being a complemental tie means for each lintel block, each said tie means being on the side portions and engaging a respective lintel block and urging the lintel block into binding with the lower portion of the breast wall. 